During the catastrophe in the World Trade Center in New York on Sep. 11, 2001, caused by a terrorist attack, it became clear, once again, that persons who are located on the upper floors of buildings have no chance to be rescued. Since the possibility of getting out of a building by the elevator or stairs does not exist, or exists only insufficiently, in the case of a fire, as in other cases of catastrophe, the sole path of rescue remains through the windows, to the outside.
In addition to the possibilities indicated above, there are other approaches to rescuing persons outside of buildings, such as fire ladders, but they only make sense up to a certain building height, or, as described in DE-36 40 057-A1, endless ropes that are attached in front of the facade, into which people can hook on, in order to then slide down. Other rappelling devices, for which persons to operate these devices are required, as a rule, are shown by DE-30 28 586-C2, DE 31 42 146-A1, DE-40 19 558-A1, U.S. Pat. No. 4,493,396, or CH-4 99 988, essentially with braking devices on ropes, as by DE-195 11 117-A1. This rope and winch technology has significant disadvantages, since it is essentially not always available, or only at some locations of buildings and, as already mentioned above, frequently requires operating personnel in order to avoid malfunctions and therefore serious accidents of the persons using it.
Other systems are overhead rescue possibilities, for example in mountain rescues, in the case of bridges or high buildings, or in the rescue of people by helicopter, on which electrically operated rope winches are located, which are used to pull the person to be rescued up on a rope; this is a method that is generally much more complicated than the ones described above.